Manufacture of incandescent electric lamps



(No Model.)

T. B. ATTE'RBUR'Y.

MANUFACTURE OF INOANDESUBNT ELECTRIC LAMPS.

No. 574,370. Patented Jan. 5-, 1897.

UNITED STATES PATENT OFFICE.

TnoMAs B. ATTERBURY, or rr'rrsnune, PENNSYLVANIA.

MANUFACTURE OF INCANDESCENT ELECTRIC LAMPS.

SPECIFICATION forming part of Letters Patent No. 574,370, dated January5, 1897. Application filed December 18, 1894. Serial No, 532,207. (Nomodel.)

To all whom it may concern:

Be it known that I, THOMAS B. ATTERBURY, of Pittsburg, in the county ofAllegheny and State of Pennsylvania, have invented a new and usefulImprovement in the Manufacture of Incandescent Electric Lamps, of whichthe following is a full, clear, and exact description, reference beinghad to the accompanying drawings, forming part of this specification, inwhich- Figure 1 is a sectional view of an incandescent electric lampconstructed in accordance with my invention and partly broken away, andFigs. 2 and 3 are top plan and vertical views of the stopper employed byme.

My invention relates to the manufacture of stopper incandescent lamps;and it has for its objects, first, to dispense with the trouble andexpense of grinding the stopper and the bulb-neck of the lamp, as hasbeen usual heretofore in the construction of lamps of thischaracter;second, to greatly decrease the expense of making the stopper; third, toprevent the formation of bubbles about the leading-in wires, and,fourth, to provide a lamp which is as durable and efficient as anall-glass lamp and also permits of the removal of the stopper and theinsertion of a new stopper and filament, if found necessary ordesirable.

I11 carrying out my invention in its preferred form I first press thestopper shown in Figs. 2 and 3, a mold being preferably employed forthis purpose which forms a large number of these articles simultan eously. This stopper, as shown, consists of a disk 2, having holes 3 for theinsertion of the leading-in wires with which the filament is connected.These holes are preferably tapered, as shown, to fit thecorrespondiugly-tapered base portions of the wires, and around each holeis preferably formed an annular rim or boss 4: for the purpose ofretaining the ocmenting material in position about the wires. The wiresare then placed in the holes and the stopper inserted in the bulb-neckof the lamp. Vitrifiable enamel or cement is then filled in above thestopper and around the leading-in wires and the article is heated tofuse and vitrify the enamel, which then serves to both secure the wiresin the stopper and the stopper in the neck of the lamp, as indicated inFig. 1..

The vitrifiable enamel or cement which I employ in carrying out myinvention may be of any composition Well known'in the arts which isfound to be suitable for use in connection with the particular kind orquality of glass of which the lamp-bulb is composed, and it may beapplied in such form as is found most advantageous in practice, both asregards convenience of manipulation and ready fusibility. The particularenamel employed in any case must obviously be fusible at a lowertemperature than the glass of which the bulb-neck and stopper arecomposed, and it should also obviously have substantially the samecoefficient of expansion when subjected to changes in temperature, forthe reason that any inequality in the expansion of the enamel and theparts which it unites would tend to resultin rupture of.

the parts and consequent destruction of the vacuum in the lamp-bulb.

The advantages of my invention will be apparent to those skilled in theart, since the formation of bubbles between the glass and the leading-inwires, which often occurred when the stopper was pressed about thewires, is entirely obviated.

A less quantity of glass is employed in making the stopper, and as nosuch accuracy in fit between the stopper and the bulb-neck is requiredas is necessary when the stopper and bulb-neck are ground together theexpense of manufacture is greatly reduced.

My invention not only enables me to dispense with the grinding of thestopper an d the bulb-neck, but also permits of the melting of theenamel by a suitable application of heat, and the substitution of afresh filament for one that has been burned out, if such repairing isfound necessary or desirable.

The wires may be cemented into the stopper before placing it in thelamp. If desired, the enamel used may be in the form of dry powder orother mixture, and many variations in the shape and'size of the stopper,the bulbneck, &c., may be made without departing from my invention.

I desire it to be also understood that my invention is not limited tocementing the leading-in wires into holes in the stopper, it beingintended to cover the cementing of the stopper into the bulb-neckirrespective of the char- IOO actor of the union between the leading-inWll'OS.

I claim as my invention 1. The method of making incandescent lampsconsisting in cementing an unground perforated stopper in the lamp byvitrifiable enamel or cement, and then heating to Yitrify said enamel,substantially as described.

2. The method of making incandescent lamps consisting in forming anunground stopper with holes therein, placing Wires in these holes,inserting the stopper in the lamp, filling in Yitrifiable enamel orcement above the stopper, and heating to vitrily the enamel,substantially as described.

3. The method of making incandescent lamps, consisting in pressing anunground stopper with tapered holes therein, placing the Wires in theseholes, inserting such unground stopper in the lamp, filling in enamelabove the stopper, and heating the same, substantially as described.

1. The improven'lent in the art of manulz'lcstopper and turin gincandescent electric lamps n'h ich col sists in applying vitriliableenamel or cement to the joint between the unground stopper and bulb-neckof a lamp and then heating the said parts until the enamel becomes 1'used and hermetically cements the stopper and bulbneck together,substantially as described.

5. An incandescent electric lamp comprising an un ground stopper orlilament-support, an unground bulb-neck, and a body of titreous enamelhermetically uniting the said parts, substantially as described.

6. An incandescent electric lamp co1nprising an unground stopper orfilament-smpport, a bulb-neck and a body of vitreous enamel intermediatesaid stopper and bulb-neck her-- metically uniting said parts.

In testimony whereof I have hereunto set my hand.

THOMAS ll. A'lill lltllURY.

Witnesses W. B. Corzwnr, H. L. GTLL.

